Hydraulic tube extrusion press



Nov. 7, 1967 H. H. GROOS 3,350911 HYDRAULIC TUBE EXTRUSION PRESS FiledVApril 26, 1967 2 Sheets-Sham l wm Nm @w mm .NN NNN NN Nm @N N. mN .NN

N k y? Q R N A Nov. 7, 1967 H. H. @Roos 3,350,911 HYDRAULIC TUBEEXTRUSION PRESS Filed April ze, 1967 2 sheetssheet 2 United StatesPatent O 3,350,911 HYDRAULIC TUBE EXTRUSION PRESS Horst Hans Groos,Metzkausen, Germany, assignor to Schloemann Aktiengesellschaft,Dusseldorf, Germany,

a company of Germany Filed Apr. 26, 1967, Ser. No. 633,983 Claimspriority, application Germany, Dec. 6, 1962, Sch 32,434 Claims. (Cl.72-265) ABSTRACT 0F THE DISCLOSURE The present hydraulic tube-extrusionpress includes a stationary bolster, a stationary main cylindercross-beam and rigid columns inter-connecting the cross-beam of thebolster. A billet container is arranged on the side of the bolsterfacing the cross-beam and a die holder and die are adapted to be clampedbetween the billet container and the bolster. A hollow extrusion ramwhich is co-axial with the die and the billet container is capable ofaxial movement relative to the die.

This application is a continuation in part of application Ser. No.324,988 filed Nov. 20, 1963, now abandoned.

A longitudinally movable platen is secured to the ram and means areprovided for forcing the platen and ram in a forward direction therebyextruding a billet from the container through the die.

Means are provided for piercing a billet prior to the extrusion thereofand such piercing means includes a mandrel slidable in the ram, alongitudinally slidable transverse cross-head for the mandrel, alongitudinally slidable piercing cylinder transverse cross-head, meansrigidly connecting the piercing cylinder traverse crosshead with theplaten, a piercing cylinder mounted in the piercing cylinder traversecross-head behind the pressed cylinders, a piston slidable in thepiercing cylinder and attached to the piercing mandrel traversecross-head, means embodying a mandrel holder and an intermediate rod fortransmitting a thrust from the piercing piston t0 the mandrel, mandrelreturning means operable for effecting relative motion between thepiercing cylinder traverse cross-head and the piercing mandrel traversecross-head, and at least one hydraulic assemblage defined by a pistonand cylinder, one of which components is operably relate to the maincylinder cross-beam and the other to the piercing cylinder traversecross-head for retracting jointly the piercing cylinder traversecross-head and platen.

The invention relates to a hydraulic tube extrusion press includingbillet piercing means which constitutes a longitudinally displaceablecomponent with a platen carrying an extrusion ram.

This type of assemblage is particularly eicacious in that the stroke ofthe piercing means is restricted solely to the working stroke, and anadditional idle stroke, such as is required in connection with fixedpiercing devices arranged in a known fashion behind the main cylinder,is as a consequence completely unnecessary.

In the known constructions of this particular type, the piercing meanshave been accommodated within the platen of the press and the press hasbeen made of a length sufcient to receive the piercing means. In thislatter arrangement, the distance between the cylinder cross-beam and thecounter-holder or bolster is greater by the length of the piercing meansincorporated in the platen than on presses having the piercing meansbehind the cylinder cross-beam and as a consequence, the entire press isof considerable length.

A salient object of this invention is to provide a press which willovercome the above and other objectionable features existing in the art.

Another object of the invention is to provide a hydraulic tube extrusionpress wherein for restricting the overall length of the press, thestroke of the piercing means is limited to the necessary working strokeof the mandrel.

In the area of the greatest pressing force, namely between the cylindercross-beam and the bolster for obtaining a robust construction, apositive connection of the participating means is accomplished which isas short as in presses wherein the piercing means is arranged behind thecylinder cross-beam. In the present invention, this end is achieved byreason of the fact that the piercing means is arranged behind the maincylinder in a known fashion and is rigidly connected with the pressplaten with such connection preferably being by way of piercing traversecolumns so that the piercing means is brought into its working positionby the platen with the stroke remaining restricted merely to the actualworking stroke.

It is further advantageous if the piercing cylinder traverse whichcarries the piercing cylinder is guided on a slideway and as a result,since the traverse cross-head constitutes a rigid iunit with the pressplaten canting or tilting of the latter is preventedY during operation.

According to a further development of the invention, the press platenreturning means are connected directly to the piercing cylinder traversecross-head so that additional traverses provided with slideways and therequired return linkage to the press platen or the otherwise customarydifferential pistons with their double packing spaces may be eliminated.

According to the invention the piercing cylinder traverse cross-head anda piercing traverse for guiding the mandrel holder are preferablyprovided with a. commonslideway which, in a manner known per se, is ofthe usual prismatic type, namely the guide surfaces on opposite sides ofthe press are inclined in opposite directions and in such a fashion asnot to hinder the expansion vand contraction, under the influence oftemperatures, of the members sliding thereon. The slideway for theplaten is similarly constructed for ensuring a precisely centralposition and a sleeve is secured on the platen for guiding the mandrelholder and for limiting the piercing stroke.

Further objects and advantages of the invention will become more readilyapparent to persons skilled in the art from the following detailedspecification and annexed drawings, and in which drawings:

FIGURE 1 is a longitudinal view partly in elevation and partly incross-section of a multi-cylinder tube press in the starting position, t

FIGURE 2 is a longitudinal view partly in elevation Y and partly in,cross section of the press in the working position and with thepiercing mandrel and extrusion ram advanced,

FIGURE 3 is a view of the press looking in the direction of the arrow Ain FIGURE l, and

FIGURE 4 is a sectional view taken along the line IV-IV of FIGURE 1, theview looking in the direction of the arrows.

From the drawings it will be seen that the press is provided with astationary main cylinder cross-beam 1 and a bolster or counter-holder 2which is rigidly connected with the cross-beam by means of columns 3. Alongitudinally displaceable billet container 4 is arranged on the sideof the bolsterV facing the cross-beam 1 and is pnovided with means (notshown) for clamping adie 5 and a die holder 6 against the bolster 2. Ahollow `extrusion ram 7 capable of movement toward the die S and locatedon a common axis 8 with the die is secured to a 3 platen 9. The platen 9is longitudinally displaceable on slideways 10. Press pistons 11 of fourpress cylinders arranged in the main cylinder cross-beam 1 symmetricallyabout the center of the press are connected with the platen 9. The upperand lower cylinders are denoted 11a and those to the left and right 11b.Moreover, the platen 9 is connected by four piercing traverse columns 12with a piercing cylinder traverse cross-head 13 located behind thecylinders 11a and guided upon slideways 14. Consequently, the platen 9constitutes, together with the columns 12 and the traverse cross-head13, a longitudinally displaceable rigid unit. It will ybe noted that thepress pistons 11 of the upper and lower cylinders 11a are hollow vandthe return cylinders 15 project into the hollow pistons 11 and thecylinders 15 are rigidly connected with press cylinders 11a. Piston rods16 bear against the traverse cross-head 13.

A piercing mandrel 17 arranged in the hollow ram 7 is supported by anintermediate rod 18 and a mandrel holder 19 in a piercing mandreltraverse cross-head 20 located between the cross-beam 1 and the traversecrosshead 13. This component is slidably guided upon the slideway 14.The mandrel 17 is moved forwardly by a piston 21 of a piercing cylinder22 secured in the traverse crosshead 13. The retraction of the mandrel17 is effected by a mandrel return means 23 located in the traversecrosshead 13 and connected with the traverse cross-head 20. In thepresent situation, the means 23 is dened by four hydraulically operablecylinders symmetrically arranged about the piercing cylinder 22.

In FIGURES 3 and 4, it will be seen that the slideways and 14 servingfor guiding the platen 9, traverse cross-head 13 and traverse cross-head20 are defined as plane guiding surfaces located on both sides beneaththe level of the axis 8 of the press and directed toward the latter. Asa consequence, notwithstanding thermal expansion of the componentssliding thereupon, the axes of said components are held in the axis 8 ofthe press.

To assure a better guiding of the mandrel 17 and the mandrel holder 19,a sleeve 24 is flanged to the platen 9 and end face 25 of the sleeve,together with a ring 26 mounted on holder 19 constitute a strokelimiting means for the piercing means as an entity. The mandrel 17 isadditionally connected with the intermediate rod 18 by means of acoupling 27 which at the same time constitutes a guide for the mandrel17 in the extrusion ram 7. The supply and discharge of the pressureliquid to and from the cylinders 11a and 11b is as diagrammaticallyillustrated in FIGS. l and 2 by way of pressure pipes or conduits 30,31, 32 and 33 which are connected with control valve means 34, 35, 36and 37 respectively. The control valve means are each connected by asecond port 'or aperture to a main inlet pipe or conduit 28 and by athird port or aperture to a main outlet pipe or conduit 39. Thediagrammatic illustration of the control valve means merely serves forillustrating the direction of flow of the pressure liquid in theexisting working position of the press.

The operation of the press is as follows:

Prior to the charging of the container 4 with a billet 28 to beextruded, the press is in the initial position illustrate-d in FIGURE 1and in which a billet loader (not shown) brings the billet 28 and apress plate 29 to the axis 8 of the press. The position of the controlvalve means in FIG. 1 corresponds to the last phase of the retraction ofthe press. The control valve means 35 connected with the mandrel returncylinder is shown in the admission position, whereas control valve means34 connected with the cylinder 11a is in the exhaust position. Theremaining valve means 36 and 37 are closed during this particularoperation.

The billet 28 together With the plate 29 is now pushed or forced intothe billet container 4. To accomplish this end, the control valve means34 is manipulated to its admission position an-d the control valve-rneans 35 to the exhaust position so that ram 7 by virtue of theadvance of the piston 11 pushes the billet 28 into the container 4. Dueto the fact that the traverse cross-head 13 via the columns 12 provide arigid unit with the platen 9, the piercing means, during theaforementioned pushing operation, is carried along toward the container4. Following a slight upsetting of the billet 28 and a slight retractionof the ram 7, the billet 28 is pierced. This is achieved by supplyingliquid into the piercing cylinder 22, through control valve means 37adjusted to the admission position, the control valve means 36 connectedto the mandrel return means 23 being at the same time in the exhaustposition.

After the piercing operation, the billet 28, is forced by the ram 7through the free space or hiatus between the die 5 and the mandrel 17,with the individual control valve means being shifted according to theworking position of the press illustrated in FIGURE 2. Upon theconclusion of the extrusion operation, the press cylinders 11a and 11bare relieved of pressure and the mandrel 17 returned or drawn `back toits initial position. Thereupon, the ram 7 is likewise retracted bysupplying pressure liquid to the return cylinder 15 according to theposition of the control valve means disclosed in FIGURE 1.

The invention is not to be confined to any strict conformity to theshowings in the drawings but changes or modificati-ons may be madetherein so long as the changes or modifications mark no materialdeparture from the spirit and scope of the appended claims.

I claim:

1. A hydraulic tube extrusion press including a stationary bolster, astationary main cylinder cross-beam, rigid columns connecting said maincylinder cross-beam with said bolster, a billet container arranged onthe side of said bolster facing said main cylinder cross-beam, a dieholder and a die adapted to be clamped between the billet container andthe bolster, a hollow extrusion ram coaxial with said die and said4billet container with said ram being movable axially relatively to saiddie, a longitudinally movable platen secured to said ram, stationarypress cylinders mounted in said main cylinder cross-beam, press pistonsslidable in said press cylinders and adapted upon admission of liquidunder pressure into said cylinders to force said Platen and ramforwardly thereby extruding a billet from said container through saiddie, and means for piercing a billet prior to extrusion thereof and saidpiercing means comprising, a mandrel slidably mounted in said extrusiondie, a longitudinally slidable piercing mandrel traverse cross-head, alongitudinally slidable piercing cylinder traverse cross-head, columnsrigidly connecting said piercing cylinder traverse cross-head with saidplaten, a piercing cylinder mounted in said piercing cylinder traversecross-head behind said press cylinder, a piercing piston slidablymounted in said piercing cylinder and secured to said piercing mandreltraverse cross-head, means for transmitting a thrust from said piercingpiston to said man-drel, mandrel returning means for causing relativemotion between said piercing cylinder traverse cross-head, and at leastone hydraulic means including piston and cylinder components, one ofwhich components is attached to said main cylinder cross-beam and theother of said components to said piercing cylinder traverse cross-headfor retraction of said piercing cylinder traverse cross-head and saidplaten jointly.

2. The hydraulic tube extrusion press as claimed in claim 1 in whichsaid means for transmitting a thrust from said piercing piston and saidmandrel includes a mandrel holder and an intermediate rod.

3. The hydraulic tube extrusion press as claimed in claim 1 furtherincluding slideways for guiding said platen piercing mandrel traversecross-head and piercing cylinder traverse cross-head, said slidewaysbeing located one on each side of the axis of the press below the levelof said press axis and the surfaces of said slideways being inclined atsuch an angle as not to hamper the expansion and contraction of suchcomponents under the influence of temperature changes.

4. The hydraulic tube extrusion press as claimed in claim 1 in which thehydraulic piston and cylinder means for the joint retraction of saidpiercing cylinder traverse Cross-head and said platen include returncylinders rigidly connected with and projecting into at least some ofsaid press cylinders and return pistons and piston rods slidable in saidreturn cylinders with such return piston rods when activated bearingagainst said piercing cylinder traverse cross-head.

5. The hydraulic tube extrusion press as claimed in claim 1 furtherincluding a sleeve secure-d to said platen for guiding said thrusttransmitting means, and a stroke limiting ring mounted upon said thrusttransmitting means adapted to bear against one end face of said sleeveduring the advance of said mandrel for limiting the stroke of saidmandrel.

References Cited UNITED STATES PATENTS 3,124,250 3/1964 Krause 72-2723,127,013 3/1964 Dohrn 72--272 3,197,994 8/1965 Samuel et al. 72--272CHARLES W. LANHAM, Primary Examiner. H. D. HOINKES, Assistant Examiner.1

1. A HYDRAULIC TUBE EXTRUSION PRESS INCLUDING A STATIONARY BOLSTER, ASTATIONARY MAIN CYLINDER CROSS-BEAM, RIGID COLUMNS CONNECTING SAID MAINCYLINDER CROSS-BEAM WITH SAID BOLSTER, A BILLET CONTAINER ARRANGED ONTHE SIDE OF SAID BOLSTER FACING SAID MAIN CYLINDER CROSS-BEAM, A DIEHOLDER AND A DIE ADAPTED TO BE CLAMPED BETWEEN THE BILLET CONTAINER ANDTHE BOLSTER, A HOLLOW EXTRUSION RAM COAXIAL WITH SAID DIE AND SAIDBILLET CONTAINER WITH SAID RAM BEING MOVABLE AXIALLY RELATIVELY TO SAIDDIE, A LONGITUDINALLY MOVABLE PLATEN SECURED TO SAID RAM, STATIONARYPRESS CYLINDERS MOUNTED IN SAID MAIN CYLINDER CROSS-BEAM, PRESS PISTONSSLIDABLE IN SAID PRESS CYLINDERS AND ADAPTED UPON ADMISSION OF LIQUIDUNDER PRESSURE INTO SAID CYLINDERS TO FORCE SAID PLATEN AND RAMFORWARDLY THEREBY EXTRUDING A BILLET FROM SAID CONTAINER THROUGH SAIDDIE, AND MEANS FOR PIERCING A BILLET PRIOR TO EXTRUSION THEREOF AND SAIDPIERCING MEANS COMPRISING, A MANDREL SLIDABLY MOUNTED IN SAID EXTRUSIONDIE, A LONGITUDINALLY SLIDABLE PIERCING MANDREL TRAVERSE CROSS-HEAD, ALONGITUDINALLY SLIDABLE PIERCING CYLINDER TRAVERSE CROSS-HEAD, COLUMNSRIGIDLY CONNECTING SAID PIERCING CYLINDER TRAVERSE CROSS-HEAD WITH SAIDPLATEN, A PIERCING CYLINDER MOUNTED IN SAID PIERCING CYLINDER TRAVERSECROSS-HEAD BEHIND SAID PRESS CYLINDER, A PIERCING PISTON SLIDABLYMOUNTED IN SAID PIERCING CYLINDER AND SECURED TO SAID PIERCING MANDRELTRAVERSE CROSS-HEAD, MEANS FOR TRAMSMITTING A THRUST FROM SAID PIERCINGPISTON TO SAID MANDREL, MANDREL RETURNING MEANS FOR CAUSING RELATIVEMOTION BETWEEN SAID PIERCING CYLINDER TRAVERSE CROSS-HEAD, AND AT LEASTONE HYDRAULIC MEANS INCLUDING PISTON AND CYLINDER COMPONENTS, ONE OFWHICH COMPONENTS IS ATTACHED TO SAID MAIN CYLINDER CROSS-BEAM AND THEOTHER OF SAID COMPONENTS TO SAID PIERCING CYLINDER TRAVERSE CROSS-HEADFOR RETRACTION OF SAID PIERCING CYLINDER TRAVERSE CROSS-HEAD AND SAIDPLATEN JOINTLY.